Inclusive prompt χ_c,b(1⁺⁺) production at the LHC

We study the prompt production of the χ_c(1⁺) and χ_b(1⁺) mesons at high energies. Unlike χ(0⁺,2⁺) production, χ(1⁺) mesons cannot be created at LO via the fusion of two on-mass-shell gluons, that is, gg → χ_c,b(1⁺) are not allowed. However, the available experimental data show that the cross sections for χ_c(1⁺) and χ_c(2⁺) are comparable. We therefore investigate four other χ(1⁺) production mechanisms: namely, (i) the standard NLO process gg → χ_c,b(1⁺) + g, (ii) via gluon virtuality, (iii) via gluon reggeisation and, finally, (iv) the possibility to form χ_c,b(1⁺) by the fusion of three gluons, where one extra gluon comes from another parton cascade, as in the Double Parton Scattering processes. (orig.)